Boosting the active sites of Cu/Ce0.8Zr0.2O2 catalysts through tailored precipitation method

Abstract

A reverse co-precipitation method was employed to increase the surface area of Ce0.8Zr0.2O2, resulting in boosting the active sites of Cu catalysts in the water–gas shift reaction (WGS). Active Cu sites and oxygen vacancy have been systematically controlled through the modification of physical properties and geometric configuration via a reverse co-precipitation of Ce0.8Zr0.2O2 support. The catalytic activity in WGS is primarily dependent on the number of active Cu species and is partially on the oxygen storage capacity. The kinetic results with Cu loadings revealed that the efficiency of active metal utilization was effectively enhanced by a reverse co-precipitation method, compared to the normal precipitation method, owing to the moderate metal–support interactions. The turnover frequency values were independent of Cu dispersion, highlighting the structure-insensitivity of Cu/Ce0.8Zr0.2O2 catalysts. This work suggests the possibility of controlling metal–support interactions through support synthesis methods.